Boys’ own … soldiers queuing to have books signed by Andy McNab at Tidworth Army Camp. Photograph: Martin Argles for the Guardian

Book review website Goodreads has uncovered a sharp gender divide in reading preferences, with analysis of 40,000 of its members finding that they leaned almost entirely towards selecting books by writers of their own sex.

2014 has been dubbed “the year of reading women” after a campaign by the author Joanna Walsh took off in January, but Goodreads’ data showed that male authors accounted for 90% of men’s 50 most-read titles this year. Before female writers rush to find a new male pseudonym, however, the converse is also true: according to Goodreads, “of the 50 books published in 2014 that were most read by women, 45 are by women, and five are by men”. And one of those men was Robert Galbraith, or JK Rowling.

“Ultimately, when it comes to the most popular 2014 books on Goodreads we are still sticking to our own sex,” says the reading website, as it laid out its investigation into the reading habits of 40,000 of its most active readers in 2014: 20,000 men and 20,000 women.

The analysis also found that in the first year of publication, 80% of a female author’s audience will be women, compared to 50% of a male author’s audience. But while women appear more open to reading books by both male and female authors, they like books by women more – and so do men. “On average, women rated books by women 4 out of 5 and books by men 3.8 out of 5. Surprise! Men like women authors more, too – on average men rated books by women 3.9 out of 5 and books by men 3.8 out of five,” said Goodreads.

Goodreads was prompted to perform its survey after “the #readwomen movement inspired us to take a closer look at where readers fall along gender lines”, it said in a blog laying out the results. #readwomen was kicked off by Walsh at the start of the year, asking readers to expand their literary horizons in the wake of statistics from US women in the arts organisation Vida showing a vast imbalance in the numbers of women reviewed and reviewing in today’s literary press. Walsh said yesterday that, while it was difficult to collect statistics on how many people are reading women writers, “response to #readwomen2014 on Twitter has been enthusiastic, with both men and women, including many ‘professional’ readers (ie reviewers and book bloggers) pledging to expand their reading lists in some self-defined way, whether it’s investigating a new sector of women’s writing (for me, this year, it’s been women in translation), reading 50%, or 100% women writers this year”.

Elizabeth Khuri Chandler, editor-in-chief and co-founder of Goodreads, said that Goodreads’ aim in sharing the data “was to stimulate conversation and self-reflection” and “to create a space for some friendly conversation about the subject”.

“It’s been fascinating to see our members discussing the male author/female author ratio of their own reading. For the most part, people are saying that they don’t set out to read a male author or a female author. It’s all about the book. But when they look at their reading lists, some of them are realising that maybe they might want to deliberately explore some different authors,” she said.

According to Goodreads’ data, men and women read the same number of books in 2014 if books from all publishing years are considered, but women read two times as many books published in 2014 as men.

“There is a caveat to the data we shared,” said Khuri Chandler. “We focused on men and women who are already active readers. So, we can’t say that the data covers all men and women. For our two groups, we learned that the men and women read the same amount of books. We did find, though, that with these active readers, the men did tend to gravitate to reading more male authors. But they did read some female authors too – it wasn’t all male authors. Also, it seems that our group of active male readers read books from a broader range of publishing dates than our group of active female readers. The female readers had more of a preference for the books published in 2014.”

Khuri Chandler added that, looking at the comments from readers about the Goodreads data, “some men said they felt they read more male authors because of the type of books they like to read. They thought that more male authors tended to write in the genres or about the topics that interest them than female authors. We also noticed that most people were unaware of the gender breakdown of the book they were reading. It certainly seems like an untapped area to explore.”

Walsh repeated a much passed-around quote, in which AM Homes cited another standout woman writer: “As Grace Paley once said to me, ‘Women have always done men the favour of reading their work and men have not returned the favour.”’ This didn’t, at first, seem to be borne out by Goodreads’ infographic, which showed women and men choosing books by their own sex as their favourites, said Walsh.

But she added: “It’s worth bearing in mind that the Vida statistics concentrate on literary fiction, and non-fiction, in which a bias towards books and reviews by men is clear in some publications, whereas the top Goodreads books include many crime, young adult and other titles less likely to be reviewed in the publications Vida covers.”